Forgot Password
Pentax Camera Forums Home
 

Showing results 1 to 25 of 300 Search:
Forum: Pentax SLR Lens Discussion 53 Minutes Ago  
16-50: Bad Idea?
Posted By Rondec
Replies: 31
Views: 538
A few 16-50 shots.


Tiny Waterfall by Vincent1825, on Flickr

Waterfall -- Processed in Color Efex by Vincent1825, on Flickr

Waterfall by Vincent1825, on Flickr
Forum: General Talk 58 Minutes Ago  
Coronavirus
Posted By Rondec
Replies: 1,446
Views: 28,112
If you can get a small container of antibacterial gel, I would just use that periodically. Otherwise, I think you are OK. Soap and water should be fine before handling contact lenses. Understand I am no expert, but it feels relatively easy to control if you are aware and take some precautions.
Forum: Lens Clubs 1 Hour Ago  
HD Pentax D FA 1:2.8 15-30mm ED SDM WR lens club!
Posted By Rondec
Replies: 544
Views: 72,964
Sunset on Tabor Road (DFA 15-30mm/pixel shift)

Sunset on Tabor Road by Vincent1825, on Flickr
Forum: Pentax K-1 1 Hour Ago  
Pixel Shifted Images
Posted By Rondec
Replies: 1,315
Views: 153,243
Sunset on Tabor Road (DFA 15-30mm/pixel shift)

Sunset on Tabor Road by Vincent1825, on Flickr
Forum: Lens Clubs 1 Hour Ago  
HD Pentax-D FA 24-70mm F2.8 Club
Posted By Rondec
Replies: 944
Views: 151,857
Fallen Tree (DFA 24-70 mm/pixel shift)

Fallen Tree by Vincent1825, on Flickr
Forum: Pentax K-1 1 Hour Ago  
Post your K-1 pictures!
Posted By Rondec
Replies: 28,381
Views: 2,502,844
Fallen Tree (DFA 24-70 mm/pixel shift)

Fallen Tree by Vincent1825, on Flickr

Sunset on Tabor Road (DFA 15-30mm/pixel shift)

Sunset on Tabor Road by Vincent1825, on Flickr
Forum: Pentax News and Rumors 1 Hour Ago  
HD Pentax-D FA★ 85mm f/1.4 SDM AW
Posted By Rondec
Replies: 223
Views: 15,828
Sigma makes nice lenses. It's just that they have never worked with Pentax. Tamron has a long history of making different lenses for Pentax and Tokina has licensed a number of lens designs from Pentax (most recently the 50mm Opera), but never any relationship with Sigma as far as I know.
Forum: Photographic Industry and Professionals 2 Hours Ago  
CIPA Feb 2020: Mirrorless still worse than DSLR
Posted By Rondec
Replies: 32
Views: 956
The stock market will probably bounce back quicker than the economy. It really tanked hard, maybe harder than it should have.

On the other hand, take two months off of any really productive work for most people and then the beginning of June of middle of May tell people they can "return to normal." It just feels like there are going to be plenty of hardware stores and restaurants that just never reopen because there is no money left to do so. Plenty of people will have no job to return to, although of course, plenty will have one as well.
Forum: Pentax SLR Lens Discussion 2 Hours Ago  
16-50: Bad Idea?
Posted By Rondec
Replies: 31
Views: 538
I've used the 16-50 for over a decade and it is a nice lens. I would miss the extra couple of mm on the wide side with the 18-135, but could probably make do with the 16-85. I guess I'm used to the size and it doesn't bother me, particularly because it is smaller with a K3 than my DFA 24-70 is with a K-1. I'd probably be OK with the 16-85 too, but the price for a new copy of that would be more than you are getting this one for and the size difference of 488 grams for the 16-85 and 562 grams for 16-50 wouldn't make that much difference in my shooting.

I've posted a lot of photos with the 16-50 and mostly shoot landscapes with it, so it works OK and the sealing has held up for a decade. But the others are good too.
Forum: General Talk 2 Hours Ago  
Coronavirus
Posted By Rondec
Replies: 1,446
Views: 28,112
I think odds are pretty good that there is minimal virus "in the air" during a walk. If aerosolization occurs, it is probably during forceful expiration such as coughing or loud singing (mentioned earlier) and even then, the droplets probably do not hang around for an extended period of time. I think the bigger concern is touching something with virus on it and then touching your face.

I think the idea with masks is to mainly (a) to prevent you from spreading virus if you are an asymptomatic carrier and (b) to make you more cognizant of every time you touch your face and hopefully reduce that.
Forum: Pentax News and Rumors 8 Hours Ago  
HD Pentax-D FA 70-210mm f/4 ED SDM WR
Posted By Rondec
Replies: 1,350
Views: 95,796
The 55-300 isn't an SDM lens. I'm saying the old DA * SDM lenses need new motors, sooner rather than later. I just think they probably will forego working on 60-250 for awhile since they have the 70-210 in the line up now.
Forum: General Talk 9 Hours Ago  
Coronavirus
Posted By Rondec
Replies: 1,446
Views: 28,112
My money is on there being no magic bullet treatment until the second wave comes through. That is to say that all of the purported treatments that are being tried currently reduce mortality ten to fifteen percent at most. Monoclonal antibodies are reasonable, but unlikely to be produced in huge amounts before this fall.

If you look at Tamiflu for influenza, it shortens the course of the illness 24 hours and has not been able to show much else. And that's a medication designed as an influenza antiviral medication. Nothing like taking antifungal medications and testing if they kill viruses in a culture dish.

Vaccines are the real way things like this are controlled but it will be the beginning of next year before they are truly available.
Forum: General Talk 10 Hours Ago  
Coronavirus
Posted By Rondec
Replies: 1,446
Views: 28,112
I would think with the number of worldwide infections, you should be able to recruit 10,000 patients pretty easily. I don't know if that study would have enough power to sort out all differences between treatment with and without, but it certainly would be a start.
Forum: General Talk 11 Hours Ago  
Coronavirus
Posted By Rondec
Replies: 1,446
Views: 28,112
I don't think anyone knows how plaquenil would work against COVID 19, but if it works (I don't think it does), it probably has to do with its ability to block viral replication and prevent the glycosylation of the receptor that the COVID 19 uses to enter cells. The whole immunosuppressant aspect of things is probably a red herring.

But as I said, studies are at best conflicting. The chinese released information showing that in a trial at 7 days there were no differences between hydroxychloroquine and other treatment with regard to viral clearing, but that there was one death in the hydroxychloroquine group versus none in the other.

The reality is that you need a big, double blinded study to really know about this treatment and whether it works (those are going on now in New York). If you have a hundred people with COVID 19 over 70 years old, with the best treatment, your death rate is going to 7 or 8 percent at most. If you take 60 people out of that group and divide them up (as the French study did) in an unblinded fashion and give 15 of them Plaquenil and Zithromax and 15 of them Plaquenil and 30 of them nothing, the end result is at best going to tell you that you need more study. All of the French patients survived. They just said that those on Plaquenil cleared the virus quicker.

This is a nice summary page that summarizes a bit of what we know about chloroquine and hydroxychloroquine. http://www.familyallergyasthmacare.com/2020/03/is-plaquenil-the-magic-drug-for-covid-19/
Forum: Pentax News and Rumors 11 Hours Ago  
HD Pentax-D FA 70-210mm f/4 ED SDM WR
Posted By Rondec
Replies: 1,350
Views: 95,796
I currently own two SDM lenses, neither of which has failed. The DA *16-50, which is now about 12 years old, I guess and the DA *55 which is 9 or 10 years old. Both seem to be working OK, but my DA *50-135 started getting flaky and I ended up selling it.

In the long run, Pentax needs to replace the SDM in the lenses with something else. They might be able to forego that with the 60-250 as the 70-210 is close enough, but the 16-50/50-135/55/300 all would warrant improvement in their lens drive systems and while they are at, they could tweak the optics on a couple of those, at least.
Forum: Photographic Industry and Professionals 11 Hours Ago  
CIPA Feb 2020: Mirrorless still worse than DSLR
Posted By Rondec
Replies: 32
Views: 956
I do think COVID will come back this coming winter, but I think there will (a) be people who have immunity to it and (b) a vaccine and other tools to mitigate its effects. Second time through won't be as bad as right now, but I wouldn't expect the economy to "come back on line" in many places before June and even then, levels of unemployment and bankruptcy will probably be unprecedented.
Forum: General Talk 12 Hours Ago  
Coronavirus
Posted By Rondec
Replies: 1,446
Views: 28,112
Let's be clear that Plaquenil (hydroxychloroquine) and zithromax are no magic antidote. Obviously you will read otherwise on the interwebs, but they have been using them in New York and currently have close to a 3 percent mortality rate (that is likely to swing higher, not lower over time). Beyond which, the idea that something is good for treatment does not equate to it being good for prevention. Somehow people drew a weird line there. If you take an antibiotic every day to prevent respiratory infections, odds are pretty good that you won't prevent any infections, but any infections you do get will be resistant to the antibiotic you are taking.

From what I can tell the Ivermectin is mostly an in vitro study, with a little bit of study using mice. The FDA-approved Drug Ivermectin inhibits the replication of SARS-CoV-2 in vitro - ScienceDirect This isn't to say that it won't be helpful and obviously we are going to grasp onto any straws that could prevent even a single death, but this is certainly early to be talking about as a possible treatment. One news article comments that Ivermectin has effectiveness in vitro against HIV, dengue, and influenza. Which is to stay that in a petri dish it works great, but there isn't an HIV patient on the planet who is taking ivermectin to control his or her HIV.

Vaccines are a year away. I have no doubt that there will be a vaccine and that it will be a big help. But honestly, if and when the virus came back this coming winter, the second time through wouldn't be as bad. No longer would it be a brand new virus for the whole population and some would have at least partial immunity to it.

I suppose testing is part of the answer -- Abbot has just come out with a 15 minute test and that will help considerably with timely results. The trouble now is that the US alone has run 1.5 million tests in the last couple of weeks. It is hard to ramp up production to the levels needed to get that sort of test out there. But even with testing, pretty aggressive quarantine measures are going to be the big thing to get things under control. I have read that in Kentucky, they are now instituting ankle bracelets for people who won't abide by quarantine precautions after they have had known contact with COVID 19 patients. Maybe that is an answer, although I don't know if we have enough bracelets for all of those involved.

---------- Post added 04-04-20 at 06:06 AM ----------



I was interested in this CF gene hypothesis. There was a group of scientists that did an analysis of the population of Brazil, a country where TB is still fairly endemic and compared areas with higher CF gene presence (with higher caucasian heritage) with those that did not have that. They did not find a difference in resistance to TB.

I know that there is always a feeling that a high prevalence of a genetic disease in a population must be due to some comparative advantage in fighting disease or something like that, but with regard to CF, we haven't found it yet. I do wonder if just high levels of intermarriage in small towns in Europe in the Middle Ages ended up producing weird genetic swings that we wouldn't see otherwise. (See presence of hemophilia in the royal families of Europe and some of the interesting genetic diseases found in Amish family groups).
Forum: Pentax Mirrorless Cameras 12 Hours Ago  
Pentax Mirrorless?
Posted By Rondec
Replies: 273
Views: 26,308
There is nothing magical about a shorter registration distance that makes most of your lenses smaller. Or sharper. Canon could make a similarly sized and sharp 70-200 f2.8 for their EOS mount. They won't because they are now pushing their MILC mount, but the only lenses that are going to be smaller are lenses that are close to the registration distance -- that is to say, pretty wide angle lenses in the case of the new MILC mounts.

I suppose the other thing is that with the Z Mount and RP mount the mount is wide enough that they can do f1 primes and f2 zooms, but those aren't exactly small lenses.

I would say that there is a lot more processing going on behind the scenes to make MILC lenses appear sharp while keeping size small. We know that Sony does that, but my guess is that Canon is tweaking things a bit as well.
Forum: Photographic Industry and Professionals 1 Day Ago  
CIPA Feb 2020: Mirrorless still worse than DSLR
Posted By Rondec
Replies: 32
Views: 956
I guess I don't see 50 fps as being revolutionary, but more evolutionary and completely useless. I'm sure it will come one of these days, but I would just rather have better quality images. Something more like Foveon, but without the down sides of it. But that sort of improvement isn't something that would MILC specific by any means.
Forum: General Talk 1 Day Ago  
Coronavirus
Posted By Rondec
Replies: 1,446
Views: 28,112
The whole point is that testing is taking too long. Patients have to be cleared of COVID before they can be transferred to the hospital ship. By the time the test results come back, there is often little point to transferring them to the ship.

At the same time, having a "clean" hospital probably makes a lot of sense to decompress things.

On the bright side of things, number of cases of covid should start to drop in New York in about a week, based on computer modeling. The down side is that there will probably be 700 deaths a day till then.
Forum: Lens Clubs 1 Day Ago  
HD Pentax-D FA 24-70mm F2.8 Club
Posted By Rondec
Replies: 944
Views: 151,857
Blue Flowers on the Staunton River (DFA 24-70mm/pixel shift)

Blue Flowers on the Staunton River by Vincent1825, on Flickr
Forum: Pentax K-1 1 Day Ago  
Pixel Shifted Images
Posted By Rondec
Replies: 1,315
Views: 153,243
Blue Flowers on the Staunton River (DFA 24-70mm/pixel shift)

Blue Flowers on the Staunton River by Vincent1825, on Flickr
Forum: Pentax K-1 1 Day Ago  
Post your K-1 pictures!
Posted By Rondec
Replies: 28,381
Views: 2,502,844
Blue Flowers on the Staunton River (DFA 24-70mm/pixel shift)

Blue Flowers on the Staunton River by Vincent1825, on Flickr
Forum: Pentax Mirrorless Cameras 1 Day Ago  
Pentax Mirrorless?
Posted By Rondec
Replies: 273
Views: 26,308
I think biz-engineer is right. Maybe some of it has to do with lag and refresh rates, but a lot has to do with just having your eye really close to a screen. Some of us are more sensitive to that than others.

Beyond which, what everyone keeps saying is, "Well, this top end EVF in this really expensive camera is way better than those in the past and if you haven't tried it you can't really say you don't like them." But I don't really want to spend 3000 dollars on a camera (that gets worse battery life) just so I can get a semi-acceptable viewfinder that I still don't really like.
Forum: Pentax Mirrorless Cameras 1 Day Ago  
Pentax Mirrorless?
Posted By Rondec
Replies: 273
Views: 26,308
I was speaking for myself and I shoot mainly landscapes and photos of my kids and neither one requires a silent shutter.
Search took 0.07 seconds | Showing results 1 to 25 of 300

 
Forum Jump


All times are GMT -7. The time now is 03:09 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top